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3.3vdc converter

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novice007

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I've got a 5vdc supply and need to get down to 3vdc for a supply to LED, can I use a 5vdc in / 3.3vdc out converter????
 
What are the LEDs you are using? I think you might be misunderstanding how an LED works.

An LED will have a forward voltage drop. You need to choose a resistor that provides the right current (typically 20mA) and drops enough voltage.

So if your supply is 5V, your LED drops 1.2V (typical) and you need 20mA, you get:

R = 3.8 / 0.02
R = 190

So pick something close by from a standard series, e.g. 220Ω.

There aren't really such things as "3v LEDs". You need more data to pick the resistor.
 
it's actually an LED illuminator within a push button switch, the contact rating of the switch is 24vdc @ 1A and details the LED as 3vdc @ 10mA.

I've got 5vdc within the circuit courtesy of a 24vdc / 5dcv converter for another component in the circuit,just wondering the best way to supply to the LED.
 
So if your supply is 5V, your LED drops 1.2V (typical).......
Please be accurate in your statements and examples. Only an IR LED (invisible) has a forward voltage of only 1.2V.
Red LEDs have the lowest voltage for a visible LED at 1.7V to 2.2V.
 
Please be accurate in your statements and examples. Only an IR LED (invisible) has a forward voltage of only 1.2V.
Red LEDs have the lowest voltage for a visible LED at 1.7V to 2.2V.

Sure, point taken.

Original poster, check the following pages:

Light Emitting Diodes (LEDs)
Technical LED Color Chart

And like I said before, post more information about the specific LEDs so I can help you further.
 
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